Adjustable arch form



July 8, 1958 H. e. HEIDEMAN 2,842,234

ADJUSTABLE ARCH FORM Filed June 17'. 1955 2 Sheets-Sheet 1 INVENTOR.

l/OMA'R a. fif/oi/VIA/V July 8, 1958 H. e. HEIDEMAN 2,842,234

ADJUSTABLE ARCH FORM Filed June 17. 1955 2 Sheets-Sheet 2 INVENTOR.

ATTOAA/i/J ADJUSTABLE ARCH FORM Homer G. Heidernan, Franklin Hills, Mich., assignor to Rex Roto Corporation, Detroit, Mich., a corporation of Michigan Application June 17, 1955, Serial No. 516,116 4 Claims. (Cl. 189- 37) This invention relates to an adjustable arch forma In many types of masonry construction, arches, such as for furnaces, fireplaces and the'like, are required. To build up such arches, conventional practice requires the construction of a rigid form for the arch; and the masonry is erected around this form. With such practice, each arch of a different size or shape requires the construction of a corresponding form.

It is an object of the present invention to provide an arch form which is easily adjustable so that a single form can be used for erecting arches of different shapes and sizes.

In the drawings:

Fig. 1 is a side elevational view of the arch form of this invention illustrating the manner in which it is employed for building up a masonry arch.

Fig.2 is a top elevational view of the arch form shown in Fig. 1.

Fig. 3 is a sectional view along the lines 33 in Fig. 1.

Fig. 4 is a sectional view along the lines 4-4 in Fig. 1.

Fig. 5 is a sectional view along the lines 5-5 in Fig. 1.

Fig 6 is a fragmentary perspective view of a portion of the arch form of this invention.

Fig. 7 is a sectional view along the lines 7--7 in Fig. 2.

Fig. 8 is a sectional view along the lines 88 in Fig. 2.

Fig. 9 is a sectional view along the lines 99 in Fig. 3.

Referring to the drawings, and particularly to Figs. 1 and 2, the arch form there illustrated comprises a pair of resilient frames 10 and 12 which are telescopically connected together and pivotally connected at their free ends to a substantially rigid frame 14. The frames 10 and 12 each comprise a plurality of spring steel bands 16 which extend parallel to one another in spaced apart relation. At one end, the bands 16 of each of the farmes 10 and 12 are secured as by welding to straps 18. The bands 16 of each frame receive therebetween the bands 15 of the other frame, and the straps 18 are secured to the lower face of the bands 16 so that the strap 18 on frame 10 underlies the bands 16 of frame 12 and the strap 18 on the frame 12 underlies the bands 16 of frame 10. Thus, the two frames 10 and 12 are telescopically and slidably interengaged; and the inner opposed ends thereof are prevented from being lifted upwardly relative to each other. The outer ends of the bands 16 of each frame are secured to a strap 20 in spaced apart relation as by welding or the like. Each of the straps 20 are mounted on one leg of a strap hinge 22.

The arch form of this invention includes a third frame 14. Frame 14 comprises two pairs of side rails 26, 28, and 30, 32. These rails are telescopically connected together by means of loop brackets 34 which are secured to the inner end of each of these rails. The outer ends of these rails are connected to pads 36 which form the other legs of strap hinges 22. Thus, the frames 10 and 12 are pivotally connected at their outer ends to the ends of frame 14. Rails 26, 28 and30, 32 are each formed with a plurality of regularly spaced openings 38 which are spaced apart atent 7 2,842,234 Patented July 8, 1958 a uniform fixed dimension; for example, 1 inch. At the same time, a plurality of clamping bolts '40 extend between the spaces 42 of the overlapping portions of bars 16 on frames 10 and 12. Clamping bolts 40'are provided with relatively flat heads 44 and with washers 46 and nuts 48. The heads 44 of bolts 40 overlie edge portions of adjacent bars 16 on the two frames 10 and 12, and the washers 46 and 48 underlie these edge portions of the adjacent bars 16. Thus, when the nuts 48 are tightened on the bolts 40, the two frames 10 and 12 are maintained in a fixed extended position. Likewise, when bolts such as shown at 50 are inserted through one or more pairs of registering openings 38 in the two sets of rails 26, 28and 30, 32, the frame 14 is maintained at a fixed length.

The arch form of this invention also includes a strut frame 52. Frame 52 comprises a pair of upright side legs 54 which are connected together in fixed spaced'apart relation by transverse straps 55. Each upright side leg 54 is provided with a vertically extending slot '56. The legs 54 may be formed as a single piece with the "groove 56 machined therethrough or as two individual pieces as illustrated which are connected together by welding a plate 58 to the upper ends thereof. The upper end of frame 52 is arranged to be secured to frames 10 and 12 by means of flat headed bolts 60 which extend downwardly between adjacent bands 16 and through small brackets 62 which extend between and are welded to the transverse bars 55 at the upper end of frame "52. Nuts 64 are used for clamping these members together. The lower ends of the side legs 54 extend downwardlybetween the side rails 26, 28 and 30, 32fon the opposite sides of frame 14 and are adapted to be clampedtherebetween by the bolts 5'0. 7

In employing the arch form described-for building up a masonry arch, the form may be adjusted to "the-proper shape by setting the various frames to the required dimensions of the desired arch. Let us suppose, for example, that the desired arch is to have a span of 40 inches and a rise of 12 inches. With these specifications of the arch to be constructed, the frame 14 is adjusted in length so that the distance between the ends thereof, that is, the distance between the outermost portions adjacent the hinges 22, is 4-0 inches. inserted through the registering openings 38 in the overlapping portions of the rails 26, 28 and 3t), 32. With the frame 14 thus initially adjusted, the strut frame 52 is then pushed upwardly, the groove 56 riding on bolt 50, until the vertical distance between the top surface of frames 10 and 12 and the lower edge of frame 14 is 12 inches. Then, the bolts 56 are tightened to hold the strut frame 52 in this position and the nuts 48 on the bolts 44 are tightened to clamp the two frames 10 and 12 together in fixed relation. The bands 16, which are preferably formed of hardened spring steel, will then assume the proper arcuate shape of the desired arch. After the side pillars 66 of the arch opening are built up to the proper height, the arch form of this invention is then supported at the proper elevation such as by bricks 68 as shown in Fig. l; and the masonry arch, which, for example, may be formed of bricks 70, may then be built around and supported on frames 10 and 12. After the masonry has set, the arch form may be removed; and if desired, it may be collapsed by loosening bolts 44 and 50.

It will also be appreciated that in order to set up the form of this invention, it is not necessary that the dimension corresponding to the rise of the arch is a known dimension. Any two dimensions of the arch are sufiicient for enabling the form to be set up to produce the desired size and shape of arch. For example, if the circumferential extent of the arch is a known dimension and the cord One or more bolts 50 are then length is also a known dimension, the arch form may be set up by simply initially securing the frames 10 and 12 together so that their combined length equals the circumferential extent of the arch and then adjusting frame 14 to the desired cord length of the arch. This willautomatically produce the desired size and shape of the arch, and the form may be rigidified by simply tightening bolts 50 so that the vertical strut frame 52 provides the necessary support at the center of the arch being constructed.

Thus, it will be seen that I have provided an arch form which may be simply and easily adjusted to produce any size and shape of arch within a relatively wide range. Furthermore, the arch is of economical construction; and at the same time, it can be collapsed to a very compact size and thus facilitate moving the arch form from one job to another. 7

It will be understood that bands 16 may be of any width or may even extend across the whole width of the frames 10 and 12, in which event frames 10 and 12 would comprise overlapping panels; the important feature being that the frames 10 and 12 are resilient and adjustable as to length. Thus, whenever the term frame is used herein, it is not limited to the open framework illustrated.

It will also be understood that if the arch is being constructed of conventional brick, then the width of frames 10 and 12 would preferably correspond generally to the length of a conventional brick; that is, about nine inches. However, these frames may be of any convenient width desired.

Iclaim:

1. An adjustable arch form comprising a pair of generally fiat rectangular frames each formed of a plurality of resiliently flexible flat bands, said bands being substantially wider than they are thick and extending longitudinally of said frames in spaced apart relation so that each frame is resiliently flexible in a direction perpendicular to the plane thereof, said frames being assembled together with the bands of one slidably arranged between the bands of the other whereby to form a resiliently flexible, generally planar support which is extensible, means for locking said frames together against relative 4 longitudinal movement in a desired position of extension, a second frame which is substantially rigid and also adjustable in length, mea-ns forming a pivotal connection between the opposite ends of said generally planar support and the opposite ends of said second frame and means for locking said second frame at a desired length of adjustment whereby said first frames may be adjusted in length to the circumferential extent of the arch to be formed and flexed in said position to the shape of the arch to be formed and said second frame may be extended to the chord length of said arch and locked at said length to hold the first frames in the desired shape and size of the arch to be formed.

2. An adjustable arch form as called for in claim 1 including an upright support connected to said first frames and extending transversely of the plane of said first and second frames and means for adjustably connecting said upright support with said second frame whereby to rigidly maintain said first frames in the arched position to which they are adjusted.

3. An' adjustable arch form as called for in claim 1 wherein the convex face of said first mentioned arched frames comprises an arch supporting face and wherein said pivotal connections arevdisposed radially inwardly of said convex face.

4. An adjustable arch form as called for in claim 1 wherein the end of each of said first frames opposite said pivotal connections is defined by a strap extending transversely of the end of each frame and underlying the bands of the other frame.

References Cited in the file of this patent UNITED STATES PATENTS 431,628 Trabert July 8, 1890 938,718 Smith Nov. 2, 1909 1,258,357 Nevers Mar. 5, 1918 FOREIGN PATENTS 11,073 France June 7, 1854 29,818 Germany Dec. 22, 1884 94,878 Germany Nov. 12, 1897 

